wikihurricanesforecastingfandomcom-20200214-history
West Pacific/2015/09W/Archive/19
Public advisory TROPICAL STORM CHAN-HOM PUBLIC ADVISORY NUMBER 19 WIKI-HURRICANES FORECASTING CENTER 12:00 AM JST SUN JUL 05 2015 ...CHAN-HOM INTENSIFIES AGAIN... SUMMARY OF 12:00 AM JST...15:00 UTC...INFORMATION ------------------------------------------------------------------- LOCATION...12.7N 146.3E CENTER POSITION CONFIDENCE: HIGH ABOUT 110 MI...170 KM SE OF HAGATNA, GUAM MAXIMUM SUSTAINED WINDS...50 KT...60 MPH...95 KM/H MINIMUM BAROMETRIC PRESSURE...989 MB...29.21 INCHES PRESENT MOVEMENT...wSW AT 16 KT...18 MPH...28 KM/H DISCUSSION AND 48-HOUR OUTLOOK --------------------------------------------- At 12:00 am JST, the center of Tropical Storm Chan-Hom was situated near 12.7N, 146.3E, or about 175 miles (280 km) southeast of Hagatna, Guam. Maximum sustained winds were 50 knots (60 mph, 95 km/h), with higher gusts. The minimum barometric pressure was 989 millibars (hPa; 29.21 inHg), and the cyclone was tracking north-northeast at 8 knots (9 mph, 14 km/h). Environmental conditions are suddenly becoming increasingly favorable, and steady to rapid intensification is expected throughout the forecast period. NEXT ADVISORY ------------------- Next complete advisory at 6:00 am JST. $$ Forecaster YE Discussion TROPICAL STORM CHAN-HOM PUBLIC DISCUSSION NUMBER 18 WIKI-HURRICANES FORECASTING CENTER 12:00 AM JST SUN JUL 05 2015 Tropical Storm Chan-Hom has most likely deepened over the past several hours. A well-organized ring of very cold cloud tops appears and now all of a sudden, it has that look of a typhoon ready to uhh, bomb out. A CDG CDO had formed and a CDR ring appers to be forming, and and radar imagery courtesy of NWS Guam indicates an eye-like feature. However, an 1125 AMSU pass shows that the inner core is not nearly as developed as I would like. Spiral banding has increased a bit, and this is evident on Guam radar. A 12z from JTWC yielded T3.0/45 knts and a SAB estimate from 1430z supported T3.0/45 knts. Estimates from CMISS ADT are at T3.7/59 knts, with raw values of T3.9/63 knts. JTWC ADT estimates are also T3.7.59 knts while JMA ADT estimates are T3.6/57 knts. While appearance suggests Chan-hom is near or at typhoon status, the data above supports 50 knts and nothing more, nothing less. While I am not impressed with its inner core so far, conditions have become more favorable for intensification, and given the look that it has, steady intensification is shown today, before leveling off slightly tomorrow as we wait for it to finish its inner core, which should take at most 36 hours. After that time, the party is going to start as rapid intensification is likely. As such, the RI phased of the forecast had been pushed up quite a bit. The intensities at day 3, 4, and 5 are not so certain due to the potential for eyewall replacement cycles and the question of how will Chan-hom handle those, as well as slightly colder waters. The new intensity forecast is higher than the previous and calls for the storm to achieve Category 5 intensity in four days. Chan-hom has started the highly-anticipated .The ridge north the storm is expected to re-intensify and force Chan-hom on a westward or northwestward motion. In fact, this motion may already be taking place. After 72 hours, as the system approaches the western extent of the anticyclone, the storm should turn increasingly poleward. The new track is a little more west than the last one since the GFS model has shifted west. INIT 04/1500Z 12.7N 146.3E 50 KT 60 MPH 12H 05/0000Z 14.1N 145.6E 65 KT 70 MPH 24H 05/1200Z 15.6N 144.4E 70 KT 80 MPH 36H 06/0000Z 17.0N 142.6E 75 KT 85 MPH 48H 06/1200Z 18.2N 140.5E 90 KT 105 MPH 72H 07/1200Z 21.2N 136.0E 125 KT 145 MPH 96H 08/1200Z 24.6N 132.2E 140 KT 160 MPH 120H 09/1200Z 27.2N 128.0E 130 KT 150 MPH $$ Forecaster YE